Method of and apparatus for automatic bag reversing

ABSTRACT

This invention consists of clamping both ends of a bag with a pair of clamps each composed of two clamping plates for holding the respective ends of the bag between them from the inside and outside of the bag and rotating the pair of clamps in their respective inward directions with their clamping plates holding the ends of the bag between them so that the bag is turned inside out and outside in.

United States Patent [1 1 Fukuta et al.

[111 3,779,432 Dec. 18, 1973 METHOD OF AND APPARATUS FOR AUTOMATIC BAGREVERSING [15] Inventors: Kenii Fukuta; Junichi Sekiguchi;

Rihei Miyashita, all of Yokohama; Yoshihira Matsuzaki, Chigasaki-shi;Yoshihiro Miura, Yokosuka-shi, all of Japan [73] Assignee: Agency ofIndustrial Science &

Technology, Tokyo, Japan 221 Filed: Oct. 26, 1971 211 'Appl. No.:192,459

[30] Foreign Application Priority Data 0m. 27, 1970 Japan 45/94563 Nov.l2, 1970 Japan 45/99637 [52] U.S. CI 223/39 [51 Int Cl A4 1 h 43 /Q0[56] References Cited UNITED STATES PATENTS 3,357,609 12/1967 Oberrecht223/39 2,838,216 6/1958 Beasley 223/57 9/1940 Koppel 223/40 PrimaryExaminer-George V. Larkin Attorney-Kurt Kelman 57 ABSTRACT Thisinvention consists of clamping both ends of a bag with a pair of clampseach composed of two clamping plates for holding the respective ends ofthe bag between them from the inside and outside of the bag and rotatingthe pair of clamps in their respective inward directions with theirclamping plates holding the ends of the bag between them so that the bagis turned inside out and outside in.

2 Claims, 12 Drawing Figures PAIENIEUUEE 18 1915 3.779.432

sum 5 METHOD GIF AND APPARATUS'FOR AUTOMATIC BAG REVERSING The presentinvention relates to a method of and an apparatus for turning a baginside out automatically.

The term bag as used in this specification means any bag like articlemade of two sheets of cloth, paper,

. film or other flexible material which are generally put together andsewn or joined at three sides with one side open or at two opposingsides with the other two opposing sides open to make a tubular form.

In the method of making a bag having the simplest rectangular form, atleast two sheets of the same form are placed one upon the other and sewnor joined together at three sides to make them into a bag form. The bagthus formed is pushed or pulled out of itself, i.e., everted, by turningits inside out and its outside in at the same time through the open partof the edge remaining unsewn, i.e., the opening edge. This reversingoperation i.e., everting, intended for hiding the seam or joint of a bagin its inside for better appearance is being widely used in making cuffsor collars in the sewing process of drape shirts etc. or in producingbag-like containers of synthetic high-molecular materials.

This reversing or everting operation is a complicated combination ofsuch basic operations as clamping, deformation, moving and rotation, andhas therefore been found difficult to mechanically automate andheretofore has been carried out manually especiallywherethe material ofthe bag is highly flexible or locally different in the degree offlexibility.

The main object of this invention is to provide an apparatus forautomatic reversing of a bag, by which industries producing sewnproducts as well as other in dustries can make remarkable progresstoward automation. i

Additional objects and advantages of the present invention will becomeapparent as the description proceeds in connectionwith the accompanyingdrawings in which:

FIGS. 1-5 are'diagrams illustrating the sequence of the process of thisinvention;

FIG. 6 is a perspective view of the main parts of an apparatus used forcarrying out the method of this invention;

FIG. 7 is a sectional view of the apparatus shown in FIG. 6;

FIG. 8 is a plan view ofthe apparatus shown in FIG. 6;

FIG. 9 is a sectional view of the main parts of another apparatus usedfor executing the present invention;

FIG. It) is a diagram illustrating an apparatus of this inventionprovided with auxiliary plates;

FIG. II is a plan of an apparatus used for carrying out the pretreatingprocess of this invention; and

FIG. 12 is a sectional view taken along line VIII- -VIII of FIG. 11.

FIGS. 1-5 are diagrams sequentially illustrating the steps of thereversing operation of a cuff as an example. Usually a cuff is made upof a sheet of padding and two sheets of base cloth placed upon thepadding one upon the other, all these sheets being sewn together atthree edges. When the cuff is reversed, the padding is sandwiched by thebase cloth on both sides, so that the reversing operation is the same asthat for reversing a bag made up of two sheets of base cloth.

Referring back to FIG. I, the cuff l is fed by a suitable apparatus (notshown) with its opening edge facing a pair of clamps 2. Said pair ofclamps 2 each consists of two clamping plates Sand 4 each rotatingindependently on the axis 5, the distance between said clamps beingsuitably adjusted depending on the size of cuff I to be everted.

When each plate 3 is inserted near its end of the opening edge of cuffI, it holds the cuff l by tightening through rotation, each plate 4rotates oppositely to the rotation of said plate 3 so that the both endsof thecuff I are held from the inside and outside as shown in FIG. 2.Next, as shown in FIG. 3 the clamps 2 rotate toward their point ofnearest proximity in the inward direction while still holding the cuffas the distance between the axes of the two clamps'2 is reduced untilthe clamps pass the point of nearest proximity and the cuff 1 is againtightened. After making a rotation of about 180, each clamp 2 recoversthe original interaxial distance, thus completing the reversingoperation of the cuff l as shown in FIG. 4.

The cuff I thus reversed is released from the clamps 2 by the respectivereverse operations of plates 2 and 3 and is then transferred to thefollowing step of the process by a suitable means (not shown).

The automatic bag reversing operation of this invention as stated aboveconsists of clamping the bag held in a state ready for reversing bymeans of the two clamping plates of the pair of clamps located at theright and left and, in the order shown in FIG. 1 to FIG. 5, reversingthe bag by the respective inward rotations of the clamps with the bagheld by them, releasing the bag thereafter from the clamps to completethe operation and rotating the clamps again to become ready forreceiving the feed of the next bag. Automatic reversing of bags iseffected by repeating this operation. Anembodiment of the apparatus ofthis invention will be described below in detail by referring to FIG. 6and FIG.

In the figures, the pair of clamps 2 for clamping the bag'l to bereversed ar mounted to the frame with a specified distance between themas'stated above, said distance being preliminarily adjusted dependingupon the size of the bag to be reversed.

The clamping plates 3 and 4', made of a suitable material such as metalor plastic are fitted to the circumference of the center supportingshaft 5 through arms 6 and 7 and shafts and 9 respectively so that theycan rotate independently. To the lower part of said supporting shaft 5is fitted a rotating disk 10 forming a gear along its circumference andhaving a spindle 111 on its lower face, said spindle 111 being supportedrotatably v by a slider 12. The slider 12 is fitted in the long hole 14provided in the frame 113 and is fixed at a predetermined position by arack 15 engaging with the gear formed along the circumference of therotating disk It).

The rotating disk lift is provided with two motors l7 and 1%, motor 117rotating the shaft b through the gears 19 and 2t) and the magneticclutch 211 and thus rotating clamping plate 3 about the shaft 5 andmotor lib rotating shaft 9 through the gears 23 and 24 and the magneticclutch 25 and thusrotating'the clamping plate 4 about the shaft 5. Saidplates 3 and 4 are made to rotate in either direction by appropriatelychanging the polarity of the voltage applied to motors 17, lb. Theplates are made to stop by means of the clutches.

When the clamping plate 3 is inserted near the opening edge of a bag fedby a suitable method, the clamping plate 3 moves to the end of the bagby the rotation of the motor 17 and holds the bag so as to tighten it,while at the same time the clamping plate 4 is rotated oppositely to therotation of the plate 3 by the rotation of the motor 18 and both ends ofthe bag are thus held from the inside and outside between plates 7 andplates 4 as is shown in FIG. 3.

The two clamps 3 and 4 now holding the bar are made to rotate in theinward direction by the motion of the reciprocating rack engaging theperiphery of the rotating disk 10 and the bag reversing operation isthus effected. The face on that side of the rack which forms the teethis slightly concaved and the gear provided along the periphery of therotating disk is kept in constant engagement with the rack by the spring16 provided on the slider. Thus, when the rotating disk comes to theconcave portion of the rack, it is drawn inwardly by spring 16 so thatthe two clamps approach one another while they are rotating. The spacebetween them is thereby reduced to allow for the deformation of the bag,thus ensuring perfect reversing of the bag.

After the clamps have made about a l80-degree rotation to complete thereversing operation, they return to their original position, recover theoriginal distance between them, and thus complete one cycle of the bagreversing operation.

In the aforementioned embodiment, the two clamping plates 3 and 4 rotatein directions opposite to each other to hold the bag. As shown in FIG.9, however, it

is also possible to hold the bag from the outside by rotating theeccentric cam 26 provided at the lower part of the shaft 9 whichconnects with plate 4 and lifting the plate 4 to the same level as theplate 3 after plate 3 has been inserted in the bag to hold it in atightened state. The clamps holding the bag in this way rotate in theinward direction because of the rack as described above and thereforethey turn the bag inside out.

Although motors are used as means for rotating the clamping plates inthis embodiment, other suitable means such as hydraulic or pneumaticsystems can of course be used instead. The clamping plate 4 may beinstalled at a position higher than the clamping plate 3 and pushed downto a position level with the plate 3 by hydraulic, pneumatic or othersuch suitable means.

Further as shown in FIG. 10, the clamping plates 3 and 4 may be providedwith auxiliary plates 27 above and below them; When the bag is passedbetween the clamping plates and the auxiliary plates while the bag isbeing reversed, the auxiliary plates serve to impart a specified amountof resistance to the passing bag to control the unwanted motion duringeverting and also to correct any imperfectly everted portion. Thus, theeverting operation is made more efficient and perfect. it is furtherpossible to provide the auxiliary plates with heat sources for improvingthe finish of the everted bag by hot-pressing the clamping plates onboth sides with the auxiliary plates 27 after the reversing operationhas been completed.

In case the two sheets of cloth or film composing the bag to be reversedare equal in flexibility, the bag is bent along the seam line andreversed uniformly in the reversing and post-treating operations. But ifpadding is attached to one of the sheets as in the case of a cuff orcollar in particular, the bag sometimes is not bent along the seam linebecause the two sheets are different in flexibility.

In such a case it may be impossible to reverse the bag along the seamline. in order to prevent this inconvenience, the bag is given a creasealong the seam line by means of a press or the like for easier bending.This pre-treatment will be described below with regard to a cuff creasedby a device of an embodiment shown in N68. 11 and 12.

The cuff is placed with its padding up on the press base 29 supported bythe support 20. Said press base 29 is provided with the press 28 aboveit. The press 28 which is made of a hard material such as metal has asuitable interior heating means and is of a shape similar to the seamline of the cuff placed on the press base and either has an acute-anglededge for effective creasing or is provided on its surface with aprotrusion having the same shape as the seam line. The press base onwhich the cuff is placed is made of a heat resisting and elasticmaterial like silicon rubber, and its hardness, thickness, etc. aresuitably selected according to the material to be creased. The supportfor the press base is made of a material hard enough to remain unbentwhen the pressure is applied.

To describe the process in detail, a plurality of pieces to be creasedare arranged on the press base and pressed by lowering a heated press onthem. The heating temperature and pressure of the press are suitablyselected according to the material of the pieces. For example, polyesterbags are pressed preferably at a pressure of about 2 5 kg/cm at C. Sincethe press is of the same shape or has a protrusion of the same shape asthe seam line of each of the pieces and the press base is made of anelastic material, the pressed portion sinks in the press base and theperiphery of the remaining unpressed portion rises along the press toleave a crease on the boundary, provided the pressure is applied to theparts uniformly by the press. After the pieces have been creasedsufficiently, the press is released and the parts are fed to thereversing apparatus.

If said pre-treatment is given, even bags made up of base cloths ofdifferent flexibility can be readily reversed on their seam lines.

The use of the method and apparatus of this invention in the reversingprocesses of the sewn products manufacturing and other industries canraise the efficientcy of production and make up the shortage of labor asthey automate the reversing of bags and baglike articles which have sofar been done mostly by hand.

We claim:

1. A method for everting a bag which comprises inserting a pair ofclamps along respective ends of the bag, said clamps each composed oftwo clamping plates disposed for holding respective ends of the bagtherebetween, clamping one clamping plate of each pair disposed withinthe bag and the other clamping plate disposed outside the bag, rotatingthe pair of clamps while in bag clamping position while diminishing thedistance between the pair of clamps during everting of the bag, in theextended plane of the bag and to everting position through points ofnearest proximity of the clamps until the bag is stretched to fulleverted length,,and releasing said clamping of an everted bag.

2. An apparatus for everting a bag which comprises in combination, apair of clamps, said clamps each having two clamping plates disposed forholding respective ends of a bag therebetween with one clamping plate ofeach pair disposed within the bag and the other clamping plate disposedoutside the bag, rotating means for 3,779,432 6 rotating each of saidclamps while in bag holding posiclamps during rotation, and means foropening said tion in the extended plane of the bag and to eveningposition through points of nearest proximity of the clamps until the bagis stretched to full everted length, fected' means for diminishing thedistance between said 5 clamps and for releasing the bag after evertingis ef-

1. A method for everting a bag which comprises inserting a pair ofclamps along respective ends of the bag, said clamps each composed oftwo clamping plates disposed for holding respective ends of the bagtherebetween, clamping one clamping plate of each pair disposed withinthe bag and the other clamping plate disposed outside the bag, rotatingthe pair of clamps while in bag clamping position while diminishing thedistance between the pair of clamps during everting of the bag, in theextended plane of the bag and to everting position through points ofnearest proximity of the clamps until the bag is stretched to fulleverted length, and releasing said clamping of an everted bag.
 2. Anapparatus for everting a bag which comprises in combination, a pair ofclamps, said clamps each having two clamping plates disposed for holdingrespective ends of a bag therebetween with one clamping plate of eachpair disposed within the bag and the other clamping plate disposedoutside the bag, rotating means for rotating each of said clamps whilein bag holding position in the extended plane of the bag and to evertingposition through points of nearest proximity of the clamps until the bagis stretched to full everted length, means for diminishing the distancebetween said clamps during rotation, and means for opening said clampsand for releasing the bag after everting is effected.